Sleep is a fundamental physiologic function that plays a ubiquitous role in health and illness. The Sleep Measurement Core will provide essential expertise, service and the tools required to undertake symptom science research that focuses upon sleep. Sleep measurement tools range from self report questionnaires to actigraphy to quantification of electroencephalographic (EEG) recordings of brain waveforms via polysomnography (PSG) from which to interpret sleep architecture. The Core specific aims are: (1) expand the number of research investigators involved in high quality, innovative interdisciplinary biobehavioral sleep research; (2) consult with and provide technical support to investigators desiring to integrate sleep measurement within their current program of research; and (3) develop and maintain a full array of sleep measurement tools and analysis resources in partnership with existing sleep measurement opportunities at Johns Hopkins University. This Core and Center seek to address the relationship between sleep disturbance and symptom severity, an important aspect of sleep-disease interactions that has been largely neglected. A particularly novel strength of the proposed Core is the integration of symptom modeling in the rat which permits rigorous exploration of underlying mechanisms and enhances the likelihood for translational discovery when combined with the Core's human sleep research capacity and expertise. The Core faculty are very broad in expertise, enhancing the potential for collaboration, an important factor in building a sustainable Center infrastructure.